Kā ātri un viegli apgūt reizināšanas tabulu

Reizināšana ir matemātiska darbība, ko var attēlot kā identisku terminu summu.

Vispārīgais reizināšanas princips

Piemēram, a ⋅ b (lasīt kā “a reizi b”) nozīmē, ka mēs summējam terminus a, kuru skaits ir vienāds ar b. Reizināšanas rezultātu sauc par reizinājumu.

piemēri:

• 2 ⋅ 6 = 2 + 2 + 2 + 2 + 2 + 2 = 12

  (sešas reizes divas)

• 5 ⋅ 4 = 5 + 5 + 5 + 5 = 20

  (četras reiz piecas)

• 3 ⋅ 8 = 3 + 3 + 3 + 3 + 3 + 3 + 3 + 3 = 24

  (astoņas reizes trīs)

Kā zināms, no faktoru vietu permutācijas reizinājums nemainās. Iepriekš minētajiem piemēriem izrādās:

• 6 ⋅ 2 = 6 + 6 = 12

  (divas reizes sešas)

• 4 ⋅ 5 = 4 + 4 + 4 + 4 + 4 = 20

  (piecas reiz četras)

• 8 ⋅ 3 = 8 + 8 + 8 = 24

  (trīs reizes astoņi)

Praktiski ieguvumi

Pateicoties reizināšanai, jūs varat ievērojami samazināt viena veida vienību kopējo skaitu utt. Piemēram, ja mums ir 7 iepakojumi, no kuriem katrā ir 5 pildspalvas, tad kopējo pildspalvu skaitu iegūst, reizinot šīs divi cipari:

5 ⋅ 7 = 5 + 5 + 5 + 5 + 5 + 5 + 5 = 35

(piecas pildspalvas septiņas reizes)

Reiziniet ar 0 XNUMX XNUMX

Rezultāts vienmēr ir nulle.

• 0 ⋅ 0 = 0
• 1 ⋅ 0 = 0 ⋅ 1 = 0
• 2 ⋅ 0 = 0 ⋅ 2 = 0 + 0 = 0
• 3 ⋅ 0 = 0 ⋅ 3 = 0 + 0 + 0 = 0
• 4 ⋅ 0 = 0 ⋅ 4 = 0 + 0 + 0 + 0 = 0
• 5 ⋅ 0 = 0 ⋅ 5 = 0 + 0 + 0 + 0 + 0 = 0
• 6 ⋅ 0 = 0 ⋅ 6 = 0 + 0 + 0 + 0 + 0 + 0 = 0
• 7 ⋅ 0 = 0 ⋅ 7 = 0 + 0 + 0 + 0 + 0 + 0 + 0 = 0
• 8 ⋅ 0 = 0 ⋅ 8 = 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 = 0
• 9 ⋅ 0 = 0 ⋅ 9 = 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 = 0
• 10 ⋅ 0 = 0 ⋅ 10 = 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 = 0

Reiziniet ar 1 XNUMX XNUMX

Produkts ir vienāds ar citu reizinātāju, kas nav viens.

• 1 ⋅ 1 = 1
• 2 ⋅ 1 = 2 ⋅ 1 = 2
• 3 ⋅ 1 = 3 ⋅ 1 = 3
• 4 ⋅ 1 = 4 ⋅ 1 = 4
• 5 ⋅ 1 = 5 ⋅ 1 = 5
• 6 ⋅ 1 = 6 ⋅ 1 = 6
• 7 ⋅ 1 = 7 ⋅ 1 = 7
• 8 ⋅ 1 = 8 ⋅ 1 = 8
• 9 ⋅ 1 = 9 ⋅ 1 = 9
• 10 ⋅ 1 = 10 ⋅ 1 = 10

Reiziniet ar 2 XNUMX XNUMX

Pievienojiet pirmo faktoru sev.

• 1 ⋅ 2 = 1 + 1 = 2
• 2 ⋅ 2 = 2 + 2 = 4
• 3 ⋅ 2 = 3 + 3 = 6
• 4 ⋅ 2 = 4 + 4 = 8
• 5 ⋅ 2 = 5 + 5 = 10
• 6 ⋅ 2 = 6 + 6 = 12
• 7 ⋅ 2 = 7 + 7 = 14
• 8 ⋅ 2 = 8 + 8 = 16
• 9 ⋅ 2 = 9 + 9 = 18
• 10 ⋅ 2 = 10 + 10 = 20

Reiziniet ar 3 XNUMX XNUMX

Pirmo koeficientu reizinām ar 2, pēc tam pievienojam rezultātam.

• 1 ⋅ 3 = (1 ⋅ 2) + 1 = 2 + 1 = 3
• 2 ⋅ 3 = (2 ⋅ 2) + 2 = 4 + 2 = 6
• 3 ⋅ 3 = (3 ⋅ 2) + 3 = 6 + 3 = 9
• 4 ⋅ 3 = (4 ⋅ 2) + 4 = 8 + 4 = 12
• 5 ⋅ 3 = (5 ⋅ 2) + 5 = 10 + 5 = 15
• 6 ⋅ 3 = (6 ⋅ 2) + 6 = 12 + 6 = 18
• 7 ⋅ 3 = (7 ⋅ 2) + 7 = 14 + 7 = 21
• 8 ⋅ 3 = (8 ⋅ 2) + 8 = 16 + 8 = 24
• 9 ⋅ 3 = (9 ⋅ 2) + 9 = 18 + 9 = 27
• 10 ⋅ 3 = (10 ⋅ 2) + 10 = 20 + 10 = 30

Reiziniet ar 4 XNUMX XNUMX

Divkāršotajam pirmajam koeficientam pievienojam tādu pašu summu.

• 1 ⋅ 4 = (1 ⋅ 2) + (1 ⋅ 2) = 2 + 2 = 4
• 2 ⋅ 4 = (2 ⋅ 2) + (2 ⋅ 2) = 4 + 4 = 8
• 3 ⋅ 4 = (3 ⋅ 2) + (3 ⋅ 2) = 6 + 6 = 12
• 4 ⋅ 4 = (4 ⋅ 2) + (4 ⋅ 2) = 8 + 8 = 16
• 5 ⋅ 4 = (5 ⋅ 2) + (5 ⋅ 2) = 10 + 10 = 20
• 6 ⋅ 4 = (6 ⋅ 2) + (6 ⋅ 2) = 12 + 12 = 24
• 7 ⋅ 4 = (7 ⋅ 2) + (7 ⋅ 2) = 14 + 14 = 28
• 8 ⋅ 4 = (8 ⋅ 2) + (8 ⋅ 2) = 16 + 16 = 32
• 9 ⋅ 4 = (9 ⋅ 2) + (9 ⋅ 2) = 18 + 18 = 36
• 10 ⋅ 4 = (10 ⋅ 2) + (10 ⋅ 2) = 20 + 20 = 40

Reiziniet ar 5 XNUMX XNUMX

Ja otrs reizinātājs ir pāra skaitlis, rezultāts beigsies ar nulli, ja nepāra, ar skaitli 5.

• 1 ⋅ 5 = 5 ⋅ 1 = 5
• 2 ⋅ 5 = 5 ⋅ 2 = 5 + 5 = 10
• 3 ⋅ 5 = 5 ⋅ 3 = (5 ⋅ 2) + 5 = 15
• 4 ⋅ 5 = 5 ⋅ 4 = (5 ⋅ 2) + (5 ⋅ 2) = 20
• 5 ⋅ 5 = 5 + 5 + 5 + 5 + 5 = 25
• 6 ⋅ 5 = 5 ⋅ 6 = (5 ⋅ 5) + 5 = 30
• 7 ⋅ 5 = 5 ⋅ 7 = 5 + 5 + 5 + 5 + 5 + 5 + 5 = 35
• 8 ⋅ 5 = 5 ⋅ 8 = (5 ⋅ 4) + (5 ⋅ 4) = 40
• 9 ⋅ 5 = 5 ⋅ 9 = (5 ⋅ 10) – 5 = 45
• 10 ⋅ 5 = 5 ⋅ 10 = 50

Reiziniet ar 6 XNUMX XNUMX

Mēs reizinām pirmo koeficientu ar 5, pēc tam pievienojam tam rezultātu.

• 1 ⋅ 6 = (1 ⋅ 5) + 1 = 5 + 1 = 6
• 2 ⋅ 6 = (2 ⋅ 5) + 2 = 10 + 2 = 12
• 3 ⋅ 6 = (3 ⋅ 5) + 3 = 15 + 3 = 18
• 4 ⋅ 6 = (4 ⋅ 5) + 4 = 20 + 4 = 24
• 5 ⋅ 6 = (5 ⋅ 5) + 5 = 25 + 5 = 30
• 6 ⋅ 6 = (6 ⋅ 5) + 6 = 30 + 6 = 36
• 7 ⋅ 6 = (7 ⋅ 5) + 7 = 35 + 7 = 42
• 8 ⋅ 6 = (8 ⋅ 5) + 8 = 40 + 8 = 48
• 9 ⋅ 6 = (9 ⋅ 5) + 9 = 45 + 9 = 54
• 10 ⋅ 6 = (10 ⋅ 5) + 10 = 50 + 10 = 60

Reiziniet ar 7 XNUMX XNUMX

Nav vienkāršota algoritma reizināšanai ar 7, tāpēc mēs izmantojam metodes, kas piemērojamas citiem faktoriem.

• 1 ⋅ 7 = 7 ⋅ 1 = 7
• 2 ⋅ 7 = 7 ⋅ 2 = 7 + 7 = 14
• 3 ⋅ 7 = 7 ⋅ 3 = (7 ⋅ 2) + 7 = 21
• 4 ⋅ 7 = 7 ⋅ 4 = (7 ⋅ 2) + (7 ⋅ 2) = 28
• 5 ⋅ 7 = 7 ⋅ 5 = 7 + 7 + 7 + 7 + 7 = 35
• 6 ⋅ 7 = 7 ⋅ 6 = (7 ⋅ 5) + 7 = 42
• 7 ⋅ 7 = 7 + 7 + 7 + 7 + 7 + 7 + 7 = 49
• 8 ⋅ 7 = 7 ⋅ 8 = (7 ⋅ 4) + (7 ⋅ 4) = 56
• 9 ⋅ 7 = 7 ⋅ 9 = (7 ⋅ 10) – 7 = 63
• 10 ⋅ 7 = 70

Reiziniet ar 8 XNUMX XNUMX

Mēs reizinām pirmo koeficientu ar 4, pēc tam pievienojam rezultātam tādu pašu summu.

• 1 ⋅ 8 = (1 ⋅ 4) + (1 ⋅ 4) = 8
• 2 ⋅ 8 = (2 ⋅ 4) + (2 ⋅ 4) = 16
• 3 ⋅ 8 = (3 ⋅ 4) + (3 ⋅ 4) = 24
• 4 ⋅ 8 = (4 ⋅ 4) + (4 ⋅ 4) = 32
• 5 ⋅ 8 = (5 ⋅ 4) + (5 ⋅ 4) = 40
• 6 ⋅ 8 = (6 ⋅ 4) + (6 ⋅ 4) = 48
• 7 ⋅ 8 = (7 ⋅ 4) + (7 ⋅ 4) = 56
• 8 ⋅ 8 = (8 ⋅ 4) + (8 ⋅ 4) = 64
• 9 ⋅ 8 = (9 ⋅ 4) + (9 ⋅ 4) = 72
• 10 ⋅ 8 = (10 ⋅ 4) + (10 ⋅ 4) = 80

Reiziniet ar 9 XNUMX XNUMX

Mēs reizinām pirmo koeficientu ar 10 un pēc tam atņemam to no iegūtā rezultāta.

• 1 ⋅ 9 = (1 ⋅ 10) - 1 = 10 - 1 = 9
• 2 ⋅ 9 = (2 ⋅ 10) - 2 = 20 - 2 = 18
• 3 ⋅ 9 = (3 ⋅ 10) - 3 = 30 - 3 = 27
• 4 ⋅ 9 = (4 ⋅ 10) - 4 = 40 - 4 = 36
• 5 ⋅ 9 = (5 ⋅ 10) - 5 = 50 - 5 = 45
• 6 ⋅ 9 = (6 ⋅ 10) - 6 = 60 - 6 = 54
• 7 ⋅ 9 = (7 ⋅ 10) - 7 = 70 - 7 = 63
• 8 ⋅ 9 = (8 ⋅ 10) - 8 = 80 - 8 = 72
• 9 ⋅ 9 = (9 ⋅ 10) - 9 = 90 - 9 = 81
• 10 ⋅ 9 = (10 ⋅ 10) - 10 = 100 - 10 = 90

Reiziniet ar 10 XNUMX XNUMX

Pievienojiet nulli otra reizinātāja beigām.

• 1 ⋅ 10 = 10 ⋅ 1 = 10
• 2 ⋅ 10 = 10 ⋅ 2 = 20
• 3 ⋅ 10 = 10 ⋅ 3 = 30
• 4 ⋅ 10 = 10 ⋅ 4 = 40
• 5 ⋅ 10 = 10 ⋅ 5 = 50
• 6 ⋅ 10 = 10 ⋅ 6 = 60
• 7 ⋅ 10 = 10 ⋅ 7 = 70
• 8 ⋅ 10 = 10 ⋅ 8 = 80
• 9 ⋅ 10 = 10 ⋅ 9 = 90
• 10 ⋅ 10 = 10 ⋅ 10 = 100